不用编译，执行下面三步即可
cd /etc/yum.repos.d wget http://linuxsoft.cern.ch/cern/scl/slc6-scl.repo yum -y --nogpgcheck install devtoolset-3-gcc devtoolset-3-gcc-c++
安装到了以下目录
/opt/rh/devtoolset-3/root/usr/bin
现在建立修改原来的gcc到现在的gcc
[root@10-149-11-152 bin]# pwd /opt/rh/devtoolset-3/root/usr/bin [root@10-149-11-152 bin]# cd /usr/bin/ [root@10-149-11-152 bin]# gcc --version gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11) Copyright (C) 2010 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. [root@10-149-11-152 bin]# cp gcc gcc-4.4.7 [root@10-149-11-152 bin]# c++ --version c++ (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11) Copyright (C) 2010 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. [root@10-149-11-152 bin]# cp c++ c++-4.4.7 [root@10-149-11-152 bin]# rm gcc rm: remove regular file `gcc'? y [root@10-149-11-152 bin]# rm c++ rm: remove regular file `c++'? y [root@10-149-11-152 bin]# ln -s /opt/rh/devtoolset-3/root/usr/bin/gcc /usr/bin/gcc [root@10-149-11-152 bin]# ln -s /opt/rh/devtoolset-3/root/usr/bin/c++ /usr/bin/c++ [root@10-149-11-152 bin]# gcc --version gcc (GCC) 4.9.1 20140922 (Red Hat 4.9.1-10) Copyright (C) 2014 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. [root@10-149-11-152 bin]# c++ --version c++ (GCC) 4.9.1 20140922 (Red Hat 4.9.1-10) Copyright (C) 2014 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.